I think you're confused on these. They do say "holds a charge for 1 year" - that is without use. If you do use them weekly, you probably have to charge them weekly or every other week. They will not maintain voltage beyond their charge capacity of 2000mAh. If your TX runs at 200mAh of draw, you need to charge every few hours.

NiMH are known for some amount of self-discharge. Interestingly, these will not self-discharge; hence the "hold charge for a year".